import { readFile } from "node:fs/promises";
import path from "node:path";

import { createClient } from "@supabase/supabase-js";

import { buildNexrenderJob } from "./nexrender-job-builder";
import type { RenderScene, RenderSettings } from "../src/lib/render-schemas";

function getSupabase() {
  const url = process.env.NEXT_PUBLIC_SUPABASE_URL;
  const key = process.env.SUPABASE_SERVICE_ROLE_KEY;
  if (!url || !key) {
    throw new Error("Supabase env vars required for render worker");
  }
  return createClient(url, key, {
    auth: { autoRefreshToken: false, persistSession: false },
  });
}

async function updateJob(
  jobId: string,
  updates: Record<string, unknown>
): Promise<void> {
  const supabase = getSupabase();
  await supabase.from("render_jobs").update(updates).eq("id", jobId);
}

async function uploadToStorage(
  jobId: string,
  filePath: string
): Promise<string> {
  const supabase = getSupabase();
  const buffer = await readFile(filePath);
  const storagePath = `${jobId}/output.mp4`;

  const { error } = await supabase.storage
    .from("renders")
    .upload(storagePath, buffer, {
      contentType: "video/mp4",
      upsert: true,
    });

  if (error) throw error;

  const { data } = supabase.storage.from("renders").getPublicUrl(storagePath);
  return data.publicUrl;
}

async function submitToNexrenderServer(
  job: ReturnType<typeof buildNexrenderJob>
): Promise<string> {
  const serverUrl = process.env.NEXRENDER_SERVER_URL;
  if (!serverUrl) {
    throw new Error("NEXRENDER_SERVER_URL not configured");
  }

  const response = await fetch(
    `${serverUrl.replace(/\/$/, "")}/api/v1/jobs`,
    {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(job),
    }
  );

  if (!response.ok) {
    throw new Error(`Nexrender server error: ${response.status}`);
  }

  const payload = (await response.json()) as { uid?: string; id?: string };
  return payload.uid ?? payload.id ?? "unknown";
}

async function renderWithCore(
  job: ReturnType<typeof buildNexrenderJob>,
  onProgress: (percent: number, message: string) => Promise<void>
): Promise<string> {
  const { render } = await import("@nexrender/core");
  const workPath =
    process.env.NEXRENDER_WORKPATH ?? path.join(process.cwd(), ".nexrender");

  await onProgress(10, "Starting After Effects render…");

  const result = await render(job, {
    workPath,
    binary: process.env.NEXRENDER_BINARY,
    skipCleanup: false,
    onProgress: (
      nexJob: { metadata?: Record<string, unknown> },
      percent: number
    ) => {
      const label = nexJob.metadata?.progressMessage as string | undefined;
      void onProgress(
        Math.min(95, Math.round(percent * 100)),
        label ?? "Rendering composition…"
      );
    },
  });

  const outputPath =
    typeof result === "string"
      ? result
      : ((result as { output?: string })?.output ??
        job.actions?.postrender?.[0]?.output);

  if (!outputPath || typeof outputPath !== "string") {
    throw new Error("Nexrender did not return output path");
  }

  return outputPath;
}

async function mockRender(
  scenes: RenderScene[],
  onProgress: (percent: number, message: string) => Promise<void>
): Promise<string> {
  const total = scenes.length;
  for (let i = 0; i < total; i += 1) {
    const percent = Math.round(((i + 1) / total) * 90);
    await onProgress(
      percent,
      `Rendering scene ${i + 1} of ${total}…`
    );
    await new Promise((resolve) => setTimeout(resolve, 800));
  }
  await onProgress(95, "Encoding MP4…");
  await new Promise((resolve) => setTimeout(resolve, 500));
  return "";
}

export async function processRenderJob(jobId: string): Promise<void> {
  const supabase = getSupabase();
  const { data: row, error } = await supabase
    .from("render_jobs")
    .select("*")
    .eq("id", jobId)
    .single();

  if (error || !row) {
    throw new Error(`Job ${jobId} not found`);
  }

  const scenes = row.scenes as RenderScene[];
  const settings = row.settings as RenderSettings;
  const totalScenes = scenes.length;

  const onProgress = async (percent: number, message: string) => {
    await updateJob(jobId, {
      status: "processing",
      progress: percent,
      progress_message: message,
    });
  };

  await updateJob(jobId, {
    status: "processing",
    progress: 2,
    progress_message: "Preparing render…",
  });

  const workDir = process.env.NEXRENDER_WORKPATH ?? path.join(process.cwd(), ".nexrender");
  const outputPath = path.join(workDir, "output", `${jobId}.mp4`);

  try {
    const nexrenderJob = buildNexrenderJob(
      scenes,
      settings,
      jobId,
      outputPath
    );

    let renderedPath = "";

    const useMock =
      process.env.RENDER_MOCK === "true" ||
      (!process.env.NEXRENDER_SERVER_URL &&
        !process.env.NEXRENDER_BINARY &&
        !process.env.NEXRENDER_TEMPLATE_SRC);

    if (useMock) {
      await mockRender(scenes, onProgress);
      await onProgress(96, "Uploading to storage…");
      const placeholder = Buffer.from(
        "Mock render — configure NEXRENDER_BINARY or RENDER_MOCK=false"
      );
      const storagePath = `${jobId}/output.mp4`;
      await supabase.storage.from("renders").upload(storagePath, placeholder, {
        contentType: "text/plain",
        upsert: true,
      });
      const { data: urlData } = supabase.storage
        .from("renders")
        .getPublicUrl(storagePath);
      await updateJob(jobId, {
        status: "completed",
        progress: 100,
        progress_message: "Render complete (mock)",
        output_url: urlData.publicUrl,
      });
      return;
    }

    if (process.env.NEXRENDER_SERVER_URL) {
      await onProgress(15, "Submitting to nexrender server…");
      const uid = await submitToNexrenderServer(nexrenderJob);
      await onProgress(25, `Nexrender job ${uid} started…`);

      for (let i = 0; i < totalScenes; i += 1) {
        await onProgress(
          25 + Math.round(((i + 1) / totalScenes) * 60),
          `Rendering scene ${i + 1} of ${totalScenes}…`
        );
        await new Promise((resolve) => setTimeout(resolve, 1200));
      }

      renderedPath = outputPath;
    } else {
      for (let i = 0; i < totalScenes; i += 1) {
        await onProgress(
          10 + Math.round((i / totalScenes) * 20),
          `Rendering scene ${i + 1} of ${totalScenes}…`
        );
      }
      renderedPath = await renderWithCore(nexrenderJob, onProgress);
    }

    await onProgress(96, "Uploading to storage…");
    const publicUrl = await uploadToStorage(jobId, renderedPath);

    await updateJob(jobId, {
      status: "completed",
      progress: 100,
      progress_message: "Render complete",
      output_url: publicUrl,
    });
  } catch (err) {
    const message =
      err instanceof Error ? err.message : "Unknown render error";
    await updateJob(jobId, {
      status: "failed",
      progress: 0,
      progress_message: "Render failed",
      error_message: message,
    });
    throw err;
  }
}